import java.util.Scanner;

public class demo1 {
    public static void main(String[] args) {
        Scanner input=new Scanner(System.in);
    int n = input.nextInt();
           int i;
            for(i=2;i<n;i++){
               if(n%i==0){
                   System.out.println(n+"不是素数");
                   break;
               }
            }
           if(i>=n){
               System.out.println(n+"是素数");
           }

    }
}
